Chromoblastomycosis Research Articles

A Good Diagnosis Saves Lives: The Importance of Teledermatology: Case Report

Chromoblastomycosis (CBM) is one of the most prevalent subcutaneous mycoses, caused by melanized or pigmented fungi. Considered a tropical or subtropical disease, commonly seen in rural areas after traumatic inoculation, mostly associated with agriculture. The lesions tend to present on the limbs and follow a chronic and progressive pattern, which if left untreated or misdiagnosed can lead to loss of functionality and lower quality of life. Teledermatology (TD) has been used mainly to diagnose, monitor and treat patients at distance in neglected areas. Guatemala has a vast rural area and despite the efforts from both private and public sectors, we still cannot reach all the patients and not all the patients can reach us. We present a case report on how with the aid of teledermatology a life was changed for the good.

Chromoblastomycosis: A Single Centre Clinical Laboratory Experience of Seven Years (2016-2022) and Literature Review From Pakistan.

Chromoblastomycosis (CBM) is a chronic infection of skin and subcutaneous tissue. CBM cases have been reported in local literature from Pakistan with heterogenous demographic, diagnostic and therapeutic information. The objective of this study is to share the experience of CBM from a large tertiary care hospital laboratory in Pakistan. This was a retrospective observational study. Histopathology and microbiology data of suspected CBM between 2016 and 2022 was retrieved. Patients' demographics, site of involvement, histopathological findings and positive microbiology cultures were assessed. Literature search on Google Scholar, PubMed and PakMediNet was done between 1990 and 2023 with multiple terms. A total of 16 CBM cases were identified; 14 were histopathology positive and two were both histopathology and culture positive. The median age was 21 years, and 11 patients were male. The predominant site was lower extremities followed by the face. Severe acanthosis, hyperkeratosis and granuloma with sclerotic bodies were observed in all histopathology slides. Alternaria spp. and Phialophora spp. were isolated from two culture-positive cases. A total of nine cases of CBM were reported from Pakistan in PubMed non-indexed journal. CBM is not a commonly thought of disease when evaluating skin lesions in Pakistan. A high index of suspicion when assessing patients who may have a history of trauma, exposure to soil and suggestive lesions is reasonable. An integrated approach between clinicians, histopathologist and microbiologist is required to do early identification and therapeutic interventions.

Improving treatment of chromoblastomycosis: the potential of COP1T-HA and antimicrobial photodynamic therapy against Fonsecaea monophora In Vitro

ABSTRACT Fonsecaea monophora is one of the common pathogenic species of Chromoblastomycosis (CBM). Antimicrobial photodynamic therapy (aPDT) shows promise as a new treatment for CBM. In this study, we evaluated the effectiveness of COP1T-HA which is a porous organic cage and aPDT against Fonsecaea spp. in vitro.

Chronic cutaneous chromoblastomycosis: A rare case

Background: Chromoblastomycosis (CBM) is a rare, chronic granulomatous and suppurative skin infection classified as a subcutaneous mycosis. CBM has a poor prognosis with a low cure rate and a high recurrence rate. The lack of scientific data regarding the diagnosis and treatment of CBM also presents a challenge for clinicians in treating this disease. Appropriate therapy can increase the cure rate and prevent disease recurrence. Case Illustration: A 66-year-old woman presented with swelling in her left arm since the last 18 years due to wood-related injuries. There were multiple well-defined hyperkeratotic verrucous plaques, papules, and nodules, measuring 6-10 cm in diameter on the left antebrachial and hand regions. Some lesions were covered with erosion and crusts. The patient also had bone malformation. Histopathological examination showed typical characteristics of CBM. The patient was treated with 100 mg Itraconazole b.i.d. for 8 months. Discussion: Clinical manifestations and histopathological examination showed typical characteristics of CBM. Bone malformation occurred due to complications in chronic cases. Facility limitations led to the inability to perform direct microscopic examination using potassium hydroxide (KOH) and fungal culture on Sabouraud's dextrose agar. After 8 weeks of treatment, the patient's lesions were improved. The patient will be evaluated every month until treatment is complete to monitor the side effects of therapy. Conclusion: CBM lesions were improved after 8 weeks of treatment. Bone malformation could occur in chronic cases. It is important to diagnose CBM correctly and provide adequate therapy for a good outcome.

Successful management of chromoblastomycosis utilizing conventional antifungal agents and imiquimod therapy

Chromoblastomycosis (CBM), a chronic fungal infection affecting the skin and subcutaneous tissues, is predominantly caused by dematiaceous fungi in tropical and subtropical areas. Characteristically, CBM presents as plaques and nodules, often leading to scarring post-healing. Besides traditional diagnostic methods such as fungal microscopy, culture, and histopathology, dermatoscopy and reflectance confocal microscopy can aid in diagnosis. The treatment of CBM is an extended and protracted process. Imiquimod, acting as an immune response modifier, boosts the host’s immune response against CBM, and controls scar hyperplasia, thereby reducing the treatment duration. We present a case of CBM in Guangdong with characteristic reflectance confocal microscopy manifestations, effectively managed through a combination of itraconazole, terbinafine, and imiquimod, shedding light on novel strategies for managing this challenging condition.

Comparison of the antifungal activity of the pyrimidine analogs flucytosine and carmofur against human-pathogenic dematiaceous fungi.

Chromoblastomycosis (CBM) and pheohyphomycosis (PHM) are the most common implantation mycoses caused by dematiaceous fungi. In the past, flucytosine (5-FC) has been used to treat CBM, but development of resistance is common. Carmofur belongs to the same class as 5-FC and has in vitro inhibitory activity against the main agents of CBM and PHM. The aim of this study was to compare the action of these two pyrimidine analog drugs against CBM and PHM agents. The minimum inhibitory concentration (MIC) and the selectivity index based on cytotoxicity tests of these two drugs against some agents of these mycoses were determined, with carmofur presenting a higher selectivity index than 5-FC. Carmofur demonstrated here synergistic interactions with itraconazole and amphotericin B against Exophiala heteromorpha, Fonsecaea pedrosoi, Fonsecaea monophora, and Fonsecaea nubica strains. Additionally, carmofur plus itraconazole demonstrated here synergism against a Phialophora verrucosa strain. To evaluate the development of carmofur resistance, passages in culture medium containing subinhibitory concentrations of this pyrimidine analog were carried out, followed by in vitro susceptibility tests. Exophiala dermatitidis quickly developed resistance, whereas F. pedrosoi took seven passages in carmofur-supplemented medium to develop resistance. Moreover, resistance was permanent in E. dermatitidis but transient in F. pedrosoi. Hence, carmofur has exhibited certain advantages, albeit accompanied by limitations such as the development of resistance, which was expected as with 5-FC. This underscores its therapeutic potential in combination with other drugs, emphasizing the need for a meticulous evaluation of its application in the fight against dematiaceous fungi.

Chromoblastomycosis in French Guiana: Epidemiology and Practices, 1955-2023.

Chromoblastomycosis (CBM) is a chronic neglected fungal disease, usually met in tropical areas. French Guiana is a South American territory with limited epidemiological data. This retrospective study concerned all patients with CBM proven by at least one paraclinical examination and diagnosed in French Guiana between 1950 and 2023. In total, 23 patients were included, mostly males (87%) of Creole origin, living in the coastal region (87%) and involved in outdoor occupations (74%). Lesions were mostly observed on the lower limbs (78.3%), with a median time to diagnosis of four years. Laboratory tests included positive direct microscopic examinations (78.3%) and mycological cultures (69.6%), identifying 14 cases of Fonsecaea pedrosoi and one case of Exophiala janselmei. Various treatments were employed, including antifungals, surgery and combinations of both. In conclusion, CBM in French Guiana involves a different population than other subcutaneous mycoses such as Lobomycosis or Paracoccidioidomycosis, mostly found in the forest hinterland. Surgery should be recommended for recent and limited lesions. Itraconazole and terbinafine should systematically be proposed, either in monotherapy or in combination with surgery or cryotherapy.

Identification of Chromoblastomycosis and Phaeohyphomycosis Agents through ITS-RFLP.

Chromoblastomycosis (CBM) and phaeohyphomycosis (FEO) are infections caused by melanized filamentous fungal agents, primarily found in tropical and subtropical regions. Both infections pose significant challenges for the correct identification of the causative agent due to their morphological similarity, making conventional methods of morphological analysis highly subjective. Therefore, molecular techniques are necessary for the precise determination of these species. In this regard, this study aimed to contribute to a new methodology based on PCR-RFLP for the identification of agents causing CBM and FEO. Sequences from the Internal Transcribed Spacer (ITS) region were used to identify potential restriction enzyme sites in silico, followed by in vitro validation using the selected restriction enzymes. The obtained results were compared with species identification through morphological analyses and sequencing. The results demonstrated that the PCR-RFLP applied in this study accurately identified two major agents of chromoblastomycosis, Fonsecaea pedrosoi and Fonsecaea monophora, as well as Cladophialophora bantiana and Exophiala dermatitidis, both causative agents of phaeohyphomycosis. In this context, the proposed assay can complement current methods for identifying these species, aiding in diagnosis, and contributing to the proper management of these infections.

Neutrophil extracellular traps (NETs) and Th-2 dominant immune responses in chronic granulomatous chromobalstomycosis.

Chromoblastomycosis (CBM), a chronic, granulomatous, suppurative mycosis of the skin and subcutaneous tissue, is caused by several dematiaceous fungi. The formation of granulomas, tissue proliferation, and fibrosis in response to these pathogenic fungi is believed to be intricately linked to host immunity. To understand this complex interaction, we conducted a comprehensive analysis of immune cell infiltrates, neutrophil extracellular traps (NETs) formation, and the fibrosis mechanism in 20 CBM lesion biopsies using immunohistochemical and immunofluorescence staining methods. The results revealed a significant infiltration of mixed inflammatory cells in CBM granulomas, prominently featuring a substantial presence of Th2 cells and M2 macrophages. These cells appeared to contribute to the production of collagen I and III in the late fibrosis mechanism, as well as NETs formation. The abundance of Th2 cytokines may act as a factor promoting the bias of macrophage differentiation toward M2, which hinders efficient fungal clearance while accelerates the proliferation of fibrous tissue. Furthermore, the expression of IL-17 was noted to recruit neutrophils, facilitating subsequent NETs formation within CBM granulomas to impede the spread of sclerotic cells. Understanding of these immune mechanisms holds promise for identifying therapeutic targets for managing chronic granulomatous CBM.

A case of chromoblastomycosis caused by Fonsecaea pedrosoi: challenge in diagnosis

Link of Video Abstract: https://youtu.be/9CxOCuDn4f4 Background: Chromoblastomycosis (CBM) is a chronic, granulomatous mycosis of the skin and subcutaneous tissue produced by the traumatic inoculation of various dematiaceous fungi. CBM lesions are clinically polymorphic and often misdiagnosed as multiple infectious and noninfectious diseases. Early diagnosis and prompt treatment of CBM are important to prevent further complications. This case study aims to evaluate the chromoblastomycosis caused by Fonsecaea pedrosoi as a challenge in diagnosis. Case Presentation: A male, 47 years old, came to the dermatovenereology clinic with a chief complaint of a wound on his right leg 17 years ago. The skin appeared thicker and scaly and felt rough. He also complained of pain and itch on the wound. Dermatological examination revealed multiple verrucous erythematous plaques, sized 10x20 cm, irregular with a well-defined and elevated border and black punctum. Results of potassium hydroxide, culture, and histopathology examination confirmed CBM with F. pedrosoi as the etiological agent. The patient was treated with a favorable outcome with oral itraconazole, local thermotherapy, and CO2 laser. Conclusion: The diagnosis of Chromoblastomycosis remains a challenge because lesions are clinically polymorphic and often misdiagnosed as various infectious and noninfectious diseases. Physicians should raise awareness of CBM as one of the differential diagnoses for chronic wounds. This case also showed that the combination treatment of itraconazole with adjuvant thermotherapy and CO2 laser had a favorable outcome.

New Immunological Markers in Chromoblastomycosis-The Importance of PD-1 and PD-L1 Molecules in Human Infection.

The pathogenesis of chromoblastomycosis (CBM) is associated with Th2 and/or T regulatory immune responses, while resistance is associated with a Th1 response. However, even in the presence of IFN-γ, fungi persist in the lesions, and the reason for this persistence is unknown. To clarify the factors associated with pathogenesis, this study aimed to determine the polarization of the cellular immune response and the densities of cells that express markers of exhaustion in the skin of CBM patients. In the skin of patients with CBM, a moderate inflammatory infiltrate was observed, characterized primarily by the occurrence of histiocytes. Analysis of fungal density allowed us to divide patients into groups that exhibited low and high fungal densities; however, the intensity of the inflammatory response was not related to mycotic loads. Furthermore, patients with CBM exhibited a significant increase in the number of CD4+ and CD8+ cells associated with a high density of IL-10-, IL-17-, and IFN-γ-producing cells, indicating the presence of a chronic and mixed cellular immune response, which was also independent of fungal load. A significant increase in the number of PD-1+ and PD-L1+ cells was observed, which may be associated with the maintenance of the fungus in the skin and the progression of the disease.

Chromoblastomycosis successfully treated with the combination of itraconazole and 5-flucytosine

Chromoblastomycosis (CBM) is a fungal disease, distributed in tropical and subtropical regions, affecting mainly rural workers. It is characterized by chronic skin lesions that may vary from nodular, tumorous, verrucous or plaque type. Associated constitutional symptoms are rarely found. The histological presentation may yield a pathognomonic feature, the Medlar (sclerotic) bodies, in which a typical brown to black pigment is depicted, explaining “copper pennies” as its alias. In this article, the case of a 56-year-old woman in the countryside of Brazil is reported; whose main complaint was a chronic leg ulcer for the past 8 years. On the left leg, a large, partially ulcerated plaque lesion was found. Microbiological cultures were positive for the pathogen. Histological analysis demonstrated pseudoepitheliomatous hyperplasia, lymphohistiocytic infiltrate and sclerotic bodies (“copper pennies”). CBM’s epidemiological panorama, once established uniquely by geographical distribution, is transitioning to a global health issue, influenced by immunosuppressive conditions, global warming and migration. This scenario demands CBM to be widely considered as a differential diagnosis and may represent a clinical challenge in regions whose professionals have little expertise in infectious tropical diseases.

Repurposing Benzimidazoles against Causative Agents of Chromoblastomycosis: Albendazole Has Superior In Vitro Activity Than Mebendazole and Thiabendazole.

Chromoblastomycosis (CBM) is a neglected human implantation mycosis caused by several dematiaceous fungal species. Currently available therapy is usually associated with physical methods, especially surgery, and with high refractoriness. Therefore, drug discovery for CBM is essential. Drug repositioning is a strategy used to facilitate the discovery of new treatments for several diseases. The aim of this study was to discover substances with antifungal activity against CBM agents from a collection of drugs previously approved for use in human diseases. A screening was performed with the NIH Clinical Collection against Fonsecaea pedrosoi. Ten substances, with clinical applicability in CBM, inhibited fungal growth by at least 60%. The minimum inhibitory concentration (MIC) of these substances was determined against other CBM agents, and the benzimidazoles albendazole, mebendazole and thiabendazole presented the lowest MIC values. The selectivity index, based on MIC and cytotoxicity of these substances, revealed albendazole to be more selective. To investigate a possible synergism of this benzimidazole with itraconazole and terbinafine, the chequerboard method was used. All interactions were classified as indifferent. Our current results suggest that benzimidazoles have repositioning potential against CBM agents. Albendazole seems to be the most promising, since it presented the highest selectivity against all dematiaceous fungi tested.

Silver(I) 1,10-Phenanthroline Complexes Are Active against Fonsecaea pedrosoi Viability and Negatively Modulate Its Potential Virulence Attributes.

The genus Fonsecaea is one of the etiological agents of chromoblastomycosis (CBM), a chronic subcutaneous disease that is difficult to treat. This work aimed to evaluate the effects of copper(II), manganese(II) and silver(I) complexes coordinated with 1,10-phenanthroline (phen)/1,10-phenanthroline-5,6-dione (phendione) on Fonsecaea spp. Our results revealed that most of these complexes were able to inhibit F. pedrosoi, F. monophora and F. nubica conidial viability with minimum inhibitory concentration (MIC) values ranging from 0.6 to 100 µM. The most effective complexes against F. pedrosoi planktonic conidial cells, the main etiologic agent of CBM, were [Ag(phen)2]ClO4 and [Ag2(3,6,9-tdda)(phen)4].EtOH, (tdda: 3,6,9-trioxaundecanedioate), displaying MIC values equal to 1.2 and 0.6 µM, respectively. These complexes were effective in reducing the viability of F. pedrosoi biofilm formation and maturation. Silver(I)-tdda-phen, combined with itraconazole, reduced the viability and extracellular matrix during F. pedrosoi biofilm development. Moreover, both silver(I) complexes inhibited either metallo- or aspartic-type peptidase activities of F. pedrosoi as well as its conidia into mycelia transformation and melanin production. In addition, the complexes induced the production of intracellular reactive oxygen species in F. pedrosoi. Taken together, our data corroborate the antifungal action of metal-phen complexes, showing they represent a therapeutic option for fungal infections, including CBM.

Analysis of the synergistic antifungal activity of everolimus and antifungal drugs against dematiaceous fungi.

Chromoblastomycosis (CBM) is a form of chronic mycosis that affects the skin and mucous membranes and is caused by species of dematiaceous fungi including Exophiala spp., Phialophora spp., and Fonsecaea spp. The persistence of this disease and limitations associated with single-drug treatment have complicated efforts to adequately manage this condition. In this study, a microdilution assay was used to explore the synergistic antifungal activity of everolimus (EVL) in combination with itraconazole (ITC), voriconazole (VRC), posaconazole (POS), and amphotericin B (AMB) against a range of clinical dematiaceous fungal isolates. These analyses revealed that the EVL+POS and EVL+ITC exhibited superior in vitro synergistic efficacy, respectively inhibiting the growth of 64% (14/22) and 59% (13/22) of tested strains. In contrast, the growth of just 9% (2/22) of tested strains was inhibited by a combination of EVL+AMB, and no synergistic efficacy was observed for the combination of EVL+VRC. Overall, these findings indicate that EVL holds promise as a novel drug that can be synergistically combined with extant antifungal drugs to improve their efficacy, thereby aiding in the treatment of CBM.

Expanding the Toolbox for Functional Genomics in Fonsecaea pedrosoi: The Use of Split-Marker and Biolistic Transformation for Inactivation of Tryptophan Synthase (trpB) Gene.

Chromoblastomycosis (CBM) is a disease caused by several dematiaceous fungi from different genera, and Fonsecaea is the most common which has been clinically isolated. Genetic transformation methods have recently been described; however, molecular tools for the functional study of genes have been scarcely reported for those fungi. In this work, we demonstrated that gene deletion and generation of the null mutant by homologous recombination are achievable for Fonsecaea pedrosoi by the use of two approaches: use of double-joint PCR for cassette construction, followed by delivery of the split-marker by biolistic transformation. Through in silico analyses, we identified that F. pedrosoi presents the complete enzymatic apparatus required for tryptophan (trp) biosynthesis. The gene encoding a tryptophan synthase trpB -which converts chorismate to trp-was disrupted. The ΔtrpB auxotrophic mutant can grow with external trp supply, but germination, viability of conidia, and radial growth are defective compared to the wild-type and reconstituted strains. The use of 5-FAA for selection of trp- phenotypes and for counter-selection of strains carrying the trp gene was also demonstrated. The molecular tools for the functional study of genes, allied to the genetic information from genomic databases, significantly boost our understanding of the biology and pathogenicity of CBM causative agents.

Inflammasome and Inflammatory Programmed Cell Death in Chromoblastomycosis.

Chromoblastomycosis (CBM) is a chronic, progressive fungal disease of the skin and subcutaneous tissue caused by a group of dematiaceous fungi. Verrucous lesions present parasite-rich granulomas and predominance of a Th2 patterns of cytokines. The inflammasome constitutes a macromolecular protein complex that play a role in the activation of caspase 1 that cleaves pro-IL1β and pro-IL18, essential mediators of inflammation, and also activates pyroptosis. We intended to explore the presence and a possible role of inflammasome elements in cutaneous human lesions in CBM, considering the expression of IL1β, IL18, caspase 1, NLRP1, and also RIPK3, a key downstream component of necroptosis signaling. 35 skin biopsies of cutaneous lesions of verrucous form of CBM and 10 biopsies from normal skin were selected. The diagnosis was based on histological and clinical analysis. An immunohistochemical protocol was performed. The histopathological analysis evidenced epidermis with hyperkeratosis, irregular acanthosis, and micro abscesses. The dermis presented suppurative granulomas and inflammatory infiltrate composed by giant cells, macrophages, epithelioid cells, lymphocytes, and some eosinophils. Positive cells were distributed in the inflammatory infiltrate, with an increased number of cells expressing caspase 1, IL1β and IL18. Cells expressing RIPK3 and NLRP1 were less frequent. The intense presence of caspase 1, IL1β and IL18, allied to NLRP1 expression, suggest that inflammasome and pyroptosis could play a role in the immune response against fungal agents of CBM. Our results, allied to data from literature, could suggest that inflammasome-mediated response and pyroptosis could be a target to be explored to decrease CBM lesions.

Chromoblastomycosis: A case series from Eastern China.

Chromoblastomycosis (CBM) is a chronic fungal infection of the cutaneous and subcutaneous tissues caused by brown pigmented fungi. Fonsecaea monophora is one of the most common pathogens of CBM in China. Most formal cases have been reported from Southern China, however, the infection is not uncommon in Eastern China where very few case series are available. To describe the clinical aspects of CBM, we report a series of 11 cases between 2018 and 2021 at a single medical center in Eastern China. The patients were predominately male (n = 9) and the disease duration ranged from 3 months to 20 years. Plaque type lesions were the most common clinical manifestations. There were 7 cases of mild forms and 3 cases of severe forms. Among the 3 severe cases, one case gave up treatment due to economic poverty; one case did not respond to a 1-year systemic treatmen; one case was cured by combination therapy of 10 months. Other cases were cured by treatment with antifungal agents. All cases of direct mycological examination were positive. All isolates were identified by morphology and sequencing of the the ITS regions of ribosomal DNA, Ten were F. monophora and 1 was Cladophialophora carrionii. All cases had been evaluated at other clinics, where 8 cases were misdiagnosed as other diseases. As a neglected tropical disease (NTD), CBM is still a major challenge in the field of dermatology, especially in its severe clinical forms. As an effective and simple diagnostic method of CBM, direct microscopic examination should be further promoted in rural hospitals.

Biofilm Formation by Chromoblastomycosis Fungi Fonsecaea pedrosoi and Phialophora verrucosa: Involvement with Antifungal Resistance.

Patients with chromoblastomycosis (CBM) suffer chronic tissue lesions that are hard to treat. Considering that biofilm is the main growth lifestyle of several pathogens and it is involved with both virulence and resistance to antimicrobial drugs, we have investigated the ability of CBM fungi to produce this complex, organized and multicellular structure. Fonsecaea pedrosoi and Phialophora verrucosa conidial cells were able to adhere on a polystyrene abiotic substrate, differentiate into hyphae and produce a robust viable biomass containing extracellular matrix. Confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) showed the tridimensional architecture of the mature biofilms, revealing a dense network of interconnected hyphae, inner channels and amorphous extracellular polymeric material. Interestingly, the co-culture of each fungus with THP-1 macrophage cells, used as a biotic substrate, induced the formation of a mycelial trap covering and damaging the macrophages. In addition, the biofilm-forming cells of F. pedrosoi and P. verrucosa were more resistant to the conventional antifungal drugs than the planktonic-growing conidial cells. The efflux pump activities of P. verrucosa and F. pedrosoi biofilms were significantly higher than those measured in conidia. Taken together, the data pointed out the biofilm formation by CBM fungi and brought up a discussion of the relevance of studies about their antifungal resistance mechanisms.

Inhibition of Melanization by Kojic Acid Promotes Cell Wall Disruption of the Human Pathogenic Fungus Fonsecaea sp.

Chromoblastomycosis (CBM) is a chronic human subcutaneous mycosis caused by various aetiologic agents. CBM does not have an established treatment but may be managed using antifungal agents, surgical removal of the lesions, or cryotherapy. Kojic acid (KA), a known tyrosinase inhibitor with a variety of biological actions, including fungistatic action against the fungus Cryptococcus neoformans, mediated by inhibiting melanin production, seems to be an alternative to improve the treatment of CBM. The aim of the present study was to analyze the action of KA against the pathogenic fungus Fonsecaea sp., an aetiological agent of CBM. The fungal culture was incubated with KA, and the amount of melanin was assessed, followed by cytochemical detection. Subsequently, the samples were analyzed by light microscopy, transmission and scanning electron microscopy. Culture analysis revealed that 100 g/mL KA significantly decreased the melanization of the fungus and the exocytosis of melanin into the culture supernatant. Additionally, KA induced less growth of biofilm formation and intense disruption of the cell wall, and decreased the number of melanin-containing vesicles in the culture supernatant. Finally, KA inhibited fungal filamentation in culture and the subsequent phagocytosis process. Thus, KA may be a promising substance to help in the treatment of CBM.